[llvm] [GlobalISel] Dump the machine function after each legalization iteration. NFC (PR #83401)

[David Green via llvm-commits]

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@@ -223,6 +223,7 @@ Legalizer::legalizeMachineFunction(MachineFunction &MF, const LegalizerInfo &LI,
   SmallVector<MachineInstr *, 128> RetryList;
   do {
     LLVM_DEBUG(dbgs() << "=== New Iteration ===\n");
+    LLVM_DEBUG(MF.dump());
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davemgreen wrote:

I often use -print-after-all along with -debug, so it shouldn't be much more than that. It should be much less than double the existing debug output for legalization. I'd expect it shouldn't do too many iterations, maybe 1-3 is common? It's just something I find useful though, I'm happy to drop this if others disagree. I can just keep adding it locally when I need it.

https://github.com/llvm/llvm-project/pull/83401